John Snow's account of the cholera outbreak in Soho, London, 1854


The source of cholera, Letter from John Snow, M.D. to the Medical Times and Gazette, September 1854

The August 1854 outbreak of cholera in Soho, London, killed 127 people in three days and 616 in total within a month. In this letter, the district doctor John Snow outlines his belief that the epidemic stemmed from ‘contamination of the water of the must frequented street-pump in Broad-street’. Snow sought a meeting with the parish Board of Guardians who agreed to disable the pump. While Snow is careful to remark that the epidemic may already have peaked by this stage, he also notes that in ‘two or three days after the use of the water was discontinued the number of fresh attacks became very few.’

This case was vital in establishing the effect of sanitation on public health, and in proving that diseases such as cholera and typhoid were carried by water. Prior to this period, it was believed that cholera was an airborne manifestation of decaying organic matter. Snow’s investigations were among the first to show that river pollution could cause widespread public health issues. As he notes at the end of this letter: ‘among the population having the impure water of the Thames, from Battersea Fields, the mortality from cholera has been ten times as great as among the population having the improved water from Thames Ditton.’

Full title:
On the mode of communication of cholera. Second edition, much enlarged
1854, London
Usage terms
Public Domain
Held by
British Library

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